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Communicable Diseases, Emergency Preparedness and Response

Influenza is a virus that causes mainly respiratory symptoms. Influenza viruses circulate seasonally each year with most illnesses occurring from November to April. Influenza viruses consists of two main types, influenza A and B; only influenza A viruses are known to have caused pandemics , which results when a new subtype appears that spreads around the world.

Infection with the influenza virus can result in a range of symptoms, from asymptomatic infection, to mild illness or more severe complications such as pneumonia or death. The most common symptoms of influenza are fever, cough, sore throat, headache and muscle aches. It is important to note that infection with other organisms can cause symptoms similar to those caused by the influenza virus.

Influenza spreads easily from person to person through coughing, sneezing, or having face-to-face contact. It can also spread when a person touches objects contaminated with the influenza virus and then touches their own eyes, mouth or nose before cleaning their hands.

Some individuals, such as young children, the elderly and those with underlying medical conditions are at highest risk of severe complications of influenza infection. The most effective way to prevent influenza infection is to receive the seasonal influenza vaccine every year.

Page last reviewed:
Page last updated: 2018-11-07 8:04 AM
Uncontrolled print copy. Valid only on day of Print: [date]
Page updated on [date/time] 2018-11-07 8:04 AM
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